Rutgers drone, at home in air and water, inspects Delaware Memorial Bridge

The use of a technology that may have been previously relegated to science fiction was announced Tuesday by the Delaware River Bay Authority (DRBA), which successfully utilized an innovative drone that can both swim and fly to conduct aerial and underwater inspections of a bridge and a ferry last month.

Developed by Rutgers University via a half-million-dollar grant from the U.S. Office of Naval Research, it is the first of its kind. It can emerge from water and then fly through the air or vice versa, recording information with the use of onboard sensors and cameras.

Scientists say the technology has both governmental and commercial uses — everything from documenting cracks in bridge piers to search and rescue operations. In the developmental stage, the units cost between $20,000 and $30,000 each, but researchers are confident that under mass production they could cost about $5,000.

"The ability to have a single autonomous vehicle inspect piers or vessels both above and below the waterline is no longer science fiction," said Thomas J. Cook, executive director of the DRBA, a bi-state agency that operates the Delaware Memorial Bridge, the Cape May-Lewes Ferry, and several corporate and aviation properties in New Jersey and Delaware.

The DRBA got to be the first to try out the unmanned vehicle — called the Naviator — between June 20 and 22 when it inspected the twin spans of the Delaware Memorial Bridge and a vessel at the Cape May Ferry Terminal in Lower Township, N.J. Though it can operate autonomously, it was tethered for the test, officials said.

Sensors and cameras on board the 2-foot-by-2-foot drone, which weighs about 10 pounds, were able to give inspectors information that would have previously required them to use a dive team, a helicopter, and a boat. It would have taken much longer to accomplish, fighting strong currents and time constraints with tides and other conditions.

Officials had hoped for pleasant weather when they scheduled the tests for late June, but instead they got somewhat choppy seas and steady winds beneath the bridge and along the bayfront near Cape May. But the Naviator apparently performed like a champ.

"Ultimately they were able to do the tests in less time with far fewer complications, with perhaps more accurate measurements and information," said F. Javier Diez, a Rutgers professor from the department of mechanical and aerospace engineering, who spent about four years developing a technology that he said scientists have dreamed about since the 1930s.

But it was trial and error in his lab that resulted in getting the propulsion, buoyancy, and control systems of the device just right, he said.

"Scientists tried for 80 years … and couldn't do it. That has been the magic of this entire thing for us," Diez said.

The Rutgers School of Engineering in New Brunswick is an official Federal Aviation Administration unmanned aerial systems testing facility. The research it is conducting is helping the FAA integrate drones safely into U.S. airspace, officials said.

Diez and his team at Rutgers worked on the amphibious drone technology in a swimming pool. Eventually he found himself in front of a panel of Navy bigwigs pitching the concept the engineers had developed using two sets of propellers, one above the other, to help the drone quickly make the tricky transition from air to water and back again.

"The magic occurs in that transition, when the drone easily gets out of the water and back in again," Diez said. "When we talked to the Navy, I heard them saying 'Wow, we've only seen this in the movies. … We didn't think this was possible. … We need this.' That's when we got our funding."

With continued interest — and money — from the government and corporate partners, Diez said the Naviator team are continuing to develop enhancements to the technology and applications for it beyond bridge inspections.

Diez said it would likely be used for ocean floor mapping; search and rescue operations, harbor and ship security, and other applications in the future. In the meantime, the Navy has requested a larger version — more than double the size — that would be able to carry a heavier payload of sensors and other equipment.

"The Naviator drone's ability to repeatedly transition from water to air in less than two seconds has opened up novel markets that will find these capabilities advantageous," said Mark Contarino, vice president of technology for SubUAS LLC, a subsidiary founded in 2016 to commercially develop and license Rutgers-patented amphibious drone technology.

Cook, of the DRBA, said the agency was happy to have participated in the first real-world use of the technology.

"Our infrastructure assets are subject to rigorous inspection programs on an annual basis, and drones have the potential to make these inspections significantly safer and more cost-efficient," Cook said.